1851361 has 4 divisors (see below), whose sum is σ = 1882800. Its totient is φ = 1819924.

The previous prime is 1851359. The next prime is 1851371. The reversal of 1851361 is 1631581.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1631581 = 7 ⋅233083.

It is a cyclic number.

It is not a de Polignac number, because 1851361 - 2¹ = 1851359 is a prime.

It is an Ulam number.

It is a Duffinian number.

1851361 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1851301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15631 + ... + 15748.

It is an arithmetic number, because the mean of its divisors is an integer number (470700).

2^1851361 is an apocalyptic number.

1851361 is the 609-th centered decagonal number.

It is an amenable number.

1851361 is a deficient number, since it is larger than the sum of its proper divisors (31439).

1851361 is an equidigital number, since it uses as much as digits as its factorization.

1851361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31438.

The product of its digits is 720, while the sum is 25.

The square root of 1851361 is about 1360.6472724406. The cubic root of 1851361 is about 122.7901991138.

The spelling of 1851361 in words is "one million, eight hundred fifty-one thousand, three hundred sixty-one".